#include <stdio.h>
#include <time.h>
#include <string.h>
#include "mymd5.h"

#define MD 5

/* GLOBAL.H - RSAREF types and constants
 */

/* PROTOTYPES should be set to one if and only if the compiler supports
 function argument prototyping.
 The following makes PROTOTYPES default to 0 if it has not already
 been defined with C compiler flags.
 */
#ifndef PROTOTYPES
#define PROTOTYPES 0
#endif

/* POINTER defines a generic pointer type */
typedef unsigned char *POINTER;

#ifdef CONFIG_USE_EXTERNAL_XELOG
/* UINT2 defines a two byte word */
typedef unsigned short int UINT2;

/* UINT4 defines a four byte word */
typedef unsigned long int UINT4;
#else
/* UINT2 defines a two byte word */
typedef unsigned short UINT2;

/* UINT4 defines a four byte word */
typedef unsigned int UINT4;

#endif

/* PROTO_LIST is defined depending on how PROTOTYPES is defined above.
 If using PROTOTYPES, then PROTO_LIST returns the list, otherwise it
 returns an empty list.
 */
#if PROTOTYPES
#define PROTO_LIST(list) list
#else
#define PROTO_LIST(list) ()
#endif

/* Length of test block, number of test blocks.
 */
#define TEST_BLOCK_LEN 1000
#define TEST_BLOCK_COUNT 1000

/* Constants for MD5Transform routine.
 */
#define S11 7
#define S12 12
#define S13 17
#define S14 22
#define S21 5
#define S22 9
#define S23 14
#define S24 20
#define S31 4
#define S32 11
#define S33 16
#define S34 23
#define S41 6
#define S42 10
#define S43 15
#define S44 21

char* MDString PROTO_LIST ((char *));
char* MDFile PROTO_LIST ((char *));
char* hmac_md5(char* text, char* key);

typedef struct
{
		UINT4 state[4]; /* state (ABCD) */
		UINT4 count[2]; /* number of bits, modulo 2^64 (lsb first) */
		unsigned char buffer[64]; /* input buffer */
} MD5_CTX;

/*void MD5Init PROTO_LIST ((MD5_CTX *));
 void MD5Update PROTO_LIST
 ((MD5_CTX *, unsigned char *, unsigned int));
 void MD5Final PROTO_LIST ((unsigned char [16], MD5_CT X *));

 static void MD5Transform PROTO_LIST ((UINT4 [4], unsigned char [64]));
 static void Encode PROTO_LIST
 ((unsigned char *, UINT4 *, unsigned int));
 static void Decode PROTO_LIST
 ((UINT4 *, unsigned char *, unsigned int));
 static void MD5_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int));
 static void MD5_memset PROTO_LIST ((POINTER, int, unsigned int));
 */
static unsigned char PADDING[64] = { 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
		0, 0, 0 };

/* F, G, H and I are basic MD5 functions.
 */
#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define I(x, y, z) ((y) ^ ((x) | (~z)))

/* ROTATE_LEFT rotates x left n bits.
 */
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))

/* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
 Rotation is separate from addition to prevent recomputation.
 */
#define FF(a, b, c, d, x, s, ac) {\
 (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac);\
 (a) = ROTATE_LEFT ((a), (s));\
 (a) += (b);\
  }
#define GG(a, b, c, d, x, s, ac) {\
 (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac);\
 (a) = ROTATE_LEFT ((a), (s));\
 (a) += (b);\
  }
#define HH(a, b, c, d, x, s, ac) {\
 (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac);\
 (a) = ROTATE_LEFT ((a), (s));\
 (a) += (b);\
  }
#define II(a, b, c, d, x, s, ac) {\
 (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac);\
 (a) = ROTATE_LEFT ((a), (s));\
 (a) += (b);\
  }
static void MD5Init(MD5_CTX *context);
static void MD5Update(MD5_CTX *context, unsigned char *input,
		unsigned int inputLen);

static void MD5Final(unsigned char digest[16], MD5_CTX *context);
static void MD5Transform(UINT4 [4], unsigned char [64]);
static void Encode(unsigned char *, UINT4 *, unsigned int);
static void Decode(UINT4 *, unsigned char *, unsigned int);
static void MD5_memcpy(POINTER, POINTER, unsigned int);
static void MD5_memset(POINTER, int, unsigned int);

/* MD5 initialization. Begins an MD5 operation, writing a new context.
 */
static void MD5Init(MD5_CTX *context)
/* context */
{
	context->count[0] = context->count[1] = 0;
	/* Load magic initialization constants.
	 */
	context->state[0] = 0x67452301;
	context->state[1] = 0xefcdab89;
	context->state[2] = 0x98badcfe;
	context->state[3] = 0x10325476;
}

/* MD5 block update operation. Continues an MD5 message-digest
 operation, processing another message block, and updating the
 context.
 */
static void MD5Update(MD5_CTX *context, unsigned char *input,
		unsigned int inputLen)
/* context */
/* input block */
/* length of input block */
{
	unsigned int i, index, partLen;

	/* Compute number of bytes mod 64 */
	index = (unsigned int)((context->count[0] >> 3) & 0x3F);

	/* Update number of bits */
	if ((context->count[0] += ((UINT4)inputLen << 3)) < ((UINT4)inputLen << 3))
		context->count[1]++;
	context->count[1] += ((UINT4)inputLen >> 29);

	partLen = 64 - index;

	/* Transform as many times as possible.
	 */
	if (inputLen >= partLen)
	{
		MD5_memcpy((POINTER)&context->buffer[index], (POINTER)input, partLen);
		MD5Transform(context->state, context->buffer);

		for (i = partLen; i + 63 < inputLen; i += 64)
			MD5Transform(context->state, &input[i]);

		index = 0;
	} else
		i = 0;

	/* Buffer remaining input */
	MD5_memcpy((POINTER)&context->buffer[index], (POINTER)&input[i], inputLen-i);
}

/* MD5 finalization. Ends an MD5 message-digest operation, writing the
 the message digest and zeroizing the context.
 */
static void MD5Final(unsigned char digest[16], MD5_CTX *context)
/* message digest */
/* context */
{
	unsigned char bits[8];
	unsigned int index, padLen;

	/* Save number of bits */
	Encode(bits, context->count, 8);

	/* Pad out to 56 mod 64.
	 */
	index = (unsigned int)((context->count[0] >> 3) & 0x3f);
	padLen = (index < 56) ? (56 - index) : (120 - index);
	MD5Update(context, (unsigned char*) PADDING, padLen);

	/* Append length (before padding) */
	MD5Update(context, bits, 8);
	/* Store state in digest */
	Encode(digest, context->state, 16);

	/* Zeroize sensitive information.
	 */
	MD5_memset((POINTER)context, 0, sizeof (*context));
}

/* MD5 basic transformation. Transforms state based on block.
 */
static void MD5Transform(UINT4 state[4], unsigned char block[64])

{

	UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];

	Decode(x, block, 64);

	/* Round 1 */
	FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
	FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
	FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
	FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
	FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
	FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
	FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
	FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
	FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
	FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
	FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
	FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
	FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
	FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
	FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
	FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */

	/* Round 2 */
	GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
	GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
	GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
	GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
	GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
	GG (d, a, b, c, x[10], S22, 0x2441453); /* 22 */
	GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
	GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
	GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
	GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
	GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
	GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
	GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
	GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
	GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
	GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */

	/* Round 3 */
	HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
	HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
	HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
	HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
	HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
	HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
	HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
	HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
	HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
	HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
	HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
	HH (b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */
	HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
	HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
	HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
	HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */

	/* Round 4 */
	II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
	II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
	II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
	II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
	II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
	II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
	II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
	II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
	II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
	II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
	II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
	II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
	II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
	II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
	II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
	II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */

	state[0] += a;
	state[1] += b;
	state[2] += c;
	state[3] += d;

	/* Zeroize sensitive information.
	 */
	MD5_memset((POINTER)x, 0, sizeof (x));
}

/* Encodes input (UINT4) into output (unsigned char). Assumes len is
 a multiple of 4.
 */
static void Encode(unsigned char *output, UINT4 *input, unsigned int len)

{
	unsigned int i, j;

	for (i = 0, j = 0; j < len; i++, j += 4)
	{
		output[j] = (unsigned char)(input[i] & 0xff);
		output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
		output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
		output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
	}
}

/* Decodes input (unsigned char) into output (UINT4). Assumes len is
 a multiple of 4.
 */
static void Decode(UINT4 *output, unsigned char *input, unsigned int len)

{
	unsigned int i, j;

	for (i = 0, j = 0; j < len; i++, j += 4)
		output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8)
				| (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
}

/* Note: Replace "for loop" with standard memcpy if possible.
 */

static void MD5_memcpy(POINTER output, POINTER input, unsigned int len)

{
	unsigned int i;

	for (i = 0; i < len; i++)
		output[i] = input[i];
}

/* Note: Replace "for loop" with standard memset if possible.
 */
static void MD5_memset(POINTER output, int value, unsigned int len)

{
	unsigned int i;

	for (i = 0; i < len; i++)
		((char *)output)[i] = (char)value;
}

/* Digests a string and prints the result.
 */
char* MDString(char *string)

{
	MD5_CTX context;
	unsigned char digest[16];
	char output1[32];
	static char output[33]= { "" };
	unsigned int len = strlen(string);
	int i;
	MD5Init(&context);
	MD5Update(&context, (unsigned char*)string, len);
	MD5Final(digest, &context);

	for (i = 0; i < 16; i++)
	{
		sprintf(&(output1[2*i]), "%02x", (unsigned char)digest[i]);
		sprintf(&(output1[2*i+1]), "%02x", (unsigned char)(digest[i]<<4));
	}
	for (i=0; i<32; i++)
		output[i]=output1[i];
	return output;
}

/* Digests a file and prints the result.
 */
char* MDFile(char *filename)
{
	static char output[33]= { "" };
	FILE *file;
	MD5_CTX context;
	int len;
	unsigned char buffer[1024], digest[16];
	int i;
	char output1[32];
	if ((file = fopen(filename, "rb")) == NULL)
	{
		printf("%s can't be openedn", filename);
		return 0;
	} else
	{
		MD5Init(&context);
		while ((len = fread(buffer, 1, 1024, file)))
			MD5Update(&context, buffer, len);
		MD5Final(digest, &context);
		fclose(file);
		for (i = 0; i < 16; i++)
		{
			sprintf(&(output1[2*i]), "%02x", (unsigned char)digest[i]);
			sprintf(&(output1[2*i+1]), "%02x", (unsigned char)(digest[i]<<4));
		}
		for (i=0; i<32; i++)
			output[i]=output1[i];		
		
		return output;
	}
}


char* hmac_md5(char* text, char* key)
{
	char digest[16];
	char output1[32];
	static char output[33]= { "" };
	MD5_CTX context;
	unsigned char k_ipad[65]; /* inner padding -
	 * key XORd with ipad
	 */
	unsigned char k_opad[65]; /* outer padding -
	 * key XORd with opad
	 */
	unsigned char tk[16];
	int i;
	int text_len = strlen(text);
	int key_len=strlen(key);
	/* if key is longer than 64 bytes reset it to key=MD5(key) */
	if (key_len > 64)
	{

		MD5_CTX tctx;

		MD5Init(&tctx);
		MD5Update(&tctx, (unsigned char*) key, key_len);
		MD5Final(tk, &tctx);

		key = (char*)tk;
		key_len = 16;
	}

	/*
	 * the HMAC_MD5 transform looks like:
	 *
	 * MD5(K XOR opad, MD5(K XOR ipad, text))
	 *
	 * where K is an n byte key
	 * ipad is the byte 0x36 repeated 64 times
	 * opad is the byte 0x5c repeated 64 times
	 * and text is the data being protected
	 */

	/* start out by storing key in pads */

	/*bzero( k_ipad, sizeof k_ipad);
	 bzero( k_opad, sizeof k_opad);
	 */

	for (i=0; i<65; i++)
		k_ipad[i]=(unsigned char)0;
	for (i=0; i<65; i++)
		k_opad[i]=(unsigned char)0;

	/*bcopy( key, k_ipad, key_len);
	 bcopy( key, k_opad, key_len);
	 */
	for (i=0; i<key_len; i++)
	{
		k_ipad[i]=(unsigned char)key[i];
		k_opad[i]=(unsigned char)key[i];
	}

	/* XOR key with ipad and opad values */
	for (i=0; i<64; i++)
	{
		k_ipad[i] ^= 0x36;
		k_opad[i] ^= 0x5c;
	}
	/*
	 * perform inner MD5
	 */
	MD5Init(&context); /* init context for 1st
	 * pass */
	MD5Update(&context, k_ipad, 64); /* start with inner pad */
	MD5Update(&context, (unsigned char*)text, text_len); /* then text of datagram

	 */
	MD5Final((unsigned char*)digest, &context); /* finish up 1st pass */
	/*
	 * perform outer MD5
	 */
	MD5Init(&context); /* init context for 2nd
	 * pass */
	MD5Update(&context, k_opad, 64); /* start with outer pad */
	MD5Update(&context, (unsigned char*) digest, 16); /* then results of 1st
	 * hash */
	MD5Final((unsigned char*)digest, &context); /* finish up 2nd pass */
	for (i = 0; i < 16; i++)
	{
		sprintf(&(output1[2*i]), "%02x", (unsigned char)digest[i]);
		sprintf(&(output1[2*i+1]), "%02x", (unsigned char)(digest[i]<<4));
	}
	for (i=0; i<32; i++)
		output[i]=output1[i];
	return output;
}

